There are many situations during a typical skiing or snowboarding day in which skiers and snowboarders would appreciate having eyes in the back of their heads. Whether cruising down a wide open slope, merging with an adjacent trail, or transiting a slope or trail on a catwalk, being able to “see” sideways or backwards provides a new level of safety to skiers and snowboarders of all abilities. Not all skiers and snowboarders are cautious or make a concerted effort to obey the rules of skiing or snowboarding etiquette. It is not uncommon to observe skiers and snowboarders of limited ability barreling down a slope out of control colliding with or nearly missing unsuspecting, controlled skiers and snowboarders on the same slope. Other skiers and snowboarders can be seen projecting themselves out of the trees at the side or bottom of a trail without concern for passing skiers or snowboarders. The same situation occurs at trail merges where the out of control skier or snowboarder on one trail could be just above an unsuspecting skier or snowboarder on the other trail as they merge. Catwalks across slopes provide multiple situations for concern. Skiers or snowboarders traversing the slope on the catwalk are vulnerable to uphill skiers or snowboarders and the uphill skiers' or snowboarders' ability to avoid them. Also in play are the skiers and snowboarders below the catwalk should the uphill skier or snowboarder decide to jump off the edge of the catwalk without seeing the skier or snowboarder below the catwalk. The uphill skier or snowboarder will be airborne when seeing the skier or snowboarder below the catwalk making it very difficult to avoid a collision.
The danger in all of the above examples can be reduced or avoided if the vulnerable skiers and snowboarders had the ability to “see” to the side or behind themselves as they proceed downhill. The ability to “see” can take many forms. Skiers or snowboarders could constantly turn their heads from side to side in search of encroaching skiers or snowboarders turning themselves into partially blind, dangerous projectiles. Skiers and snowboarders could wear rear view mirrors on their helmets to reduce the amount of time required to scan behind them. But they still need to focus on the rear view mirror; time spent not looking for other skiers or snowboarders in their own downhill path. Rear view mirrors are also susceptible to frost, fog, and snow, all of which reduce visibility and lead to periodic cleaning, an irritant taking away from the free skiing or snowboarding experience. Skiers and snowboarders could mount video cameras to the rear of their helmets and use a heads up display in their goggles to view the rearward video scene. This approach suffers the same disadvantages as the rear view mirror in addition to being very expensive.
The approach proposed in this patent allowing skiers and snowboarders to “see” beside or behind themselves avoids the problems described above. In general the proposed approach uses a rear looking radar with audio alerts. The small size, power, and weight of the radar allow it to be mounted in the helmet. The audio alert warning of an encroaching skier or snowboarder allows the skier or snowboarder to continue to look downhill while performing an evading maneuver. Evading maneuvers could be quick turns to the right or left or stops to the right or left depending on the audio alert and the situation.
There are radar warning systems for automobiles that look forward1, sideways2, and to the rear3,4,5 for example, but none fit the skiing and snowboarding applications. The skiing and snowboarding applications require small, lightweight, low dissipated power, low transmit power (to maximize user safety), limited field of view, low delay, quick reaction time, and rear looking radar detecting a forward moving target. While the inventors have not found a suitable, off-the-shelf device in the open literature, there are capable systems1 that could be modified to meet the specific skiing and snowboarding requirements. In addition, the inventors claim that a system similar to that described herein could be built with different system parameters while meeting similar requirements and objectives for the skiing/snowboarding application and for a pedestrian application. 1R. Stevenson, “A Driver's Sixth Sense,” IEEE Spectrum, October 2011, pp 50-55.2Delphi Automotive Systems, http://www.prnewswire.com/news-releases/delphis-collosion-avoidance-systems-take-accident-prevention-to-the-next-level Feb. 23, 1998.3M. Rao, “Accident Avoidance During Vehicle Backup,” U.S. Pat. No. 7,772,991 B2, Aug. 10, 2010.4B. Osborne, http://www.geek.com/articles/gadgets/audiovox-offers-easy-wireless-collision-avoidance-solution, Jun. 17, 2008.5P. Seiler, et al, “Development of a Collision Avoidance System,” Society of Automotive Engineers, 98PC-417, 1998.